The preferred method for landing an aircraft is a straight-in approach to the runway. There may be instances, however, when a straight-in approach to a runway is unavailable. In such instances, the aircraft flight crew may need to implement a so-called circle-to-land (CTL) maneuver. There may be any one of numerous reasons for which the flight crew may need to implement a CTL maneuver. For example, inclement weather or traffic around the airport may prohibit a straight in landing. Moreover, at some airports a CTL maneuver may be necessitated by limited air traffic control facilities. In other instances, although an airport may have a straight-in instrument approach procedure for certain runways, local weather conditions or other constraints may favor another runway that does not have such an approach procedure. In these latter instances, the initial approach to the airport may be straight in, but the flight crew ultimately implements a CTL maneuver. In yet other instances navigational aids (“NAVAIDS”) may direct the aircraft to the center, rather than to the end, of the runway. In these instances, the flight implements a CTL maneuver to align the aircraft with the appropriate runway.
No matter the reason for its implementation, a CTL maneuver can be challenging because of the high work load experienced by the flight crew during the maneuver. For example, a CTL maneuver is typically performed at low altitude using visual cues, such as runway lights, and is often performed manually. During a CTL maneuver, the flight crew is also responsible to maintain visual contact with the runway. Thus, if the CTL maneuver results in the aircraft circling in a direction that is opposite to the seat in which the pilot-in-control (PIC) is seated, the PIC may need to rely on the co-pilot, or other flight crew member, to keep the runway in view. In view of these responsibilities alone, it will be appreciated that the difficulty of a CTL maneuver can increase significantly in cases of poor weather, at night time, or in other conditions of low visibility.
In addition to each of the responsibilities and factors described above, during a CTL maneuver the pilot is responsible for keeping the aircraft within a defined protected air space. The protected airspace is based, for example, on the aircraft category (e.g., indicated airspeed) used during the CTL maneuver, and is typically defined, for a specific aircraft category, to be a fixed radius from the ends of each runway. However, these data, while provided on most approach charts, is not available to the flight crew in other forms. Thus, an aircraft may fly outside of the protected airspace during a CTL maneuver without the flight crew even being aware of this situation. This can significantly increase the probability of, among other things, a controlled flight into terrain (CFIT) event.
Hence, there is a need for a display system and method that displays, in real-time, the protected airspace associated with a CTL maneuver, to thereby reduce the workload on the flight crew during a CTL maneuver and/or reduce the probability of a CFIT event occurring during a CTL maneuver. The present invention addresses one or more of these needs.